I’ve spent countless hours on the internet trying to find kick-butt places to buy my materials. To meet this qualification, in general, the site must have an easy-to-use interface and require zero interaction with human beings. Price helps too.
OnlineMetals.com fits the bill for ordering copper as a substrate for plating and for ordering raw brass for cutting mats.
I order Copper Sheet 110, 19 gauge for daguerreotype plate substrates. I think that 19 gauge is about the thinnest I’ll be able to get away with. I have used plates as thick as 12 gauge before though!
The copper comes wrapped in saran wrap and generally has small scratches all over it. So as not to confuse, let me tell you that the stuff is RAW and requires considerable polishing before its ready to take to the plater. Why do I order from onlinemetals.com if I have to work so hard on it? It’s cheap, they make custom cut sizes, and they ship it out fast.
The brass that I use for mats is Brass c260 “Cartridge Brass”, 24 gauge in 12×12″ sheets. This brass is pretty thin and is shines up to a beautiful aureate finish. I cut this out on my CNC in various sizes and shapes as needed so I just buy the somewhat universal 12×12″ sheets.
Pro-tip for making mats: cut the bevel, polish it up, heat the brass until it glows purple, douse in water, then rough up the face with 60-grit sandpaper. This gives you a beautiful bi-color finish where the bevel is a dark brassy color and the face maintains the contrasting aureate finish as seen on the left.
Jonathan